Earlier this year I went on a rather unusual reporting trip: I drove the winding road across Flores, a verdant island that is part of the world’s biggest Muslim-majority country, to visit a religious institution that produces more Roman Catholic priests than anywhere else. Centuries ago Europeans brought Catholicism to this Indonesian isle. Now Flores trains so many priests that it exports them to parishes from Angola to Austria.

These missionaries in reverse are increasingly crucial to the future of the Catholic church. As interest in joining the priesthood dwindles in the West, the late Pope Francis pointed to Flores as a rare source of hope. Yet the more time I spent with the young aspiring priests, the more I wondered whether they were ready for the indifference—and sometimes hostility—they may encounter overseas. In Flores, priests are local heroes.

It didn’t take me long to realise there was something unusual about Ledalero, a training college for Catholic priests on the Indonesian island of Flores. The week began with a Mass for a dead priest in the campus’s grand chapel. A battered Casio keyboard served as a makeshift organ for a choir of young men with fresh-fade haircuts and white cassocks, accompanied by a handful of nuns. The deceased’s former classmate, dressed in purple vestments, delivered a eulogy that had the congregation in stitches. The dead priest, it turned out, liked nothing better than to get roaringly drunk with his parishioners after attending traditional ceremonies involving the drinking of pigs’ blood.